Newly Qualified Nursing in Canada

Hi there
I am a newly qualified nurse from the UK and hoping to move out to Canada to practice. I was wondering if you knew whether this is generally possible without having first worked here? Also, before I begin the registration process, do I need to be immigration cleared, or do I do that after I have registered (if I succeed)? How long does the process generally take from start to finish, as I heard that 3 years(!) is about the average. I apologise if these questions have been asked a thousand times before, but I'd be grateful for any advice!